1. Technical Field
This invention relates generally to ducting for cables and the like.
2. Relation to the Prior Art
This invention may have general application to duct work for carrying various types of lines and/or cable. It will be discussed in connection with telecommunication networks for convenience and because that may be one of its major applications.
Known telecommunications networks often include bundles of electrical or fiber optic cables. In order to route the cables to form the network, and to provide protection for the cables, it is generally known to provide a duct to guide and house the cable bundles. Because of the various curved and cornered paths which the cables may have to follow, the associated ducting must also have cornered and curved configurations. Provision of the ducts also helps to prevent accidental cutting and kinking of the cable, and help to prevent associated signal loss. Also, because a network of cables may require a bundle of cables to be split at a junction to follow multiple paths, the ducting may include various configurations of T-fittings and four-way cross connectors.
To facilitate installation, and maintenance, of a cable network, it is also generally known to provide the ducting with removable covers. Installation of the network is eased by first installing the ducts, and then removing the associated cover from the duct. The cabling can then be laid into the ducts and the covers replaced on the ducts to enclose the cabling. The provision of removable covers also eases access to the cables to facilitate maintenance of the cables, and permits a greater fill capacity of the ducts.
One of the problems associated with such ducting is that, when the covers from the duct work are removed, the cables housed by the ducts can become dislocated or fall out of the ducts due, for example, to tension in the bundles of cables which might be wrapped around corners and curves and due to gravity. Where the ducting includes a vertically oriented T-fitting, for example, the cabling can be especially susceptible to accidental dislocation from the duct when the cover is removed. A fall from the duct can result in a kink or cut in the cabling with attendant loss of the signal carried by the cable.
The wiring, and thus the ducting for the wires, is often used in cramped spaces. Therefore, the duct construction should be compact to extend its use in such spaces and, as much as possible, free of laterally, or outwardly projecting flanges.
Another problem associated with known ducting is that removal of the covers from the associated duct can loosen the fasteners for securing the cover to the duct, thereby introducing the danger of a cover inadvertently separating from the ducting and requiring greater maintenance of the communications network.